Is it necessary to have a Nessus scanner before deploying Tenable.SC?

Having a Nessus scanner before deploying Tenable Security Center (Tenable.SC) is necessary because Tenable.SC relies on data collected by the Nessus scanners to conduct vulnerability assessments and provide comprehensive security insights. The integration between Tenable.SC and Nessus is foundational, as the scanners are responsible for performing the actual vulnerability scans on systems and assets within the network.

By systematically collecting data from Nessus, Tenable.SC can aggregate, analyze, and present the vulnerability information in a centralized platform, facilitating better visibility and management of security risks. Without a Nessus scanner, Tenable.SC would lack the critical data needed to function effectively, severely limiting its capabilities in vulnerability management.

Other options suggest varying degrees of necessity for a Nessus scanner, but the core functionality of Tenable.SC is fundamentally tied to the data sourced from these scanners, emphasizing that having at least one Nessus scanner is indeed a requirement for a proper setup and deployment of Tenable.SC.